Disk harrow.



W. S. NICHOLS.

DISK HARROW.

APPLICATION FILED JULY 14, 1913.

1,092,284. Patented Apr. 7, 19M

wwydi UNITED STATES PA NT FIQE.

WINFIELD SCOTT NICHOLS, OF PLANO, ILLINOIS, ASSIGNOR TO INDEPENDENTI-IARVESTER COMPANY, OF PLANO, ILLINOIS, A. CORPORATION OF ILLINOIS.

DISK HARROW.

To all whom it may concern Be it known that I, VVINFIELD Soorr NIoHoLs,a citizen of the United States, residing at Plano, in the county ofKendall and State of Illinois, have invented new and useful Improvementsin Disk Harrows, of which the following is a specification, referencebeing had to the accompanying drawings, forming a part thereof.

The purpose of this invention is to provide an improved construction fordisk harrows to remedy a certain defect in such harrows as heretoforeconstructed. It consists of the features and elements described andshown in the drawings as indicated in the claims.

In the drawings :Figure 1 is a plan view of a part of a disk harrowembodying this invention. Fig. 2 is a detail axial section of one of thedisks equipped with the features constituting this invention.

The drawings show in a general way the ordinary construction andorganization of a disk harrow comprising two gangs of harrow disks, 1,mounted on two shafts, 2, which are mounted in the usual manner on theframe, 3, with capacity of adjustment to vary the angle at which theydiverge from perfect alinement to each other in operation. In the commonconstruction of these implements bumpers are provided at the proximateends of the shafts of the two gangs of disks which bear against eachother in the operative positions of the two gangs, and upon which in amanner the two gangs fulcrum against each other in changes of angle. Insuch construction it will be seen that the operating peripheries of theproximate disks of the two gangs which may be close together when thegangs are adjusted most divergent from alinement will be spread apartmore and more as the gangs are adjusted toward a position at which theshafts are alined. In some of these common forms the bumper is made soas to extend for a considerable distance out toward the workingperiphery of the disk on which it is mounted, in which case the twobumpers roll upon each other,their point of contact shifting from thecenter out toward the circumference,as the gangs are adjusted fromalinement to the position of their greatest divergence from alinement,but in this form also it results that the working peripheries of theproximate harrow disks are moved Specification of Letters Patent.

Application filed July 14, 1913.

which is untouched by the harrow.

Patented Apr. 7, 191a.

Serial No. 778,830.

fart-her and farther apart as the shafts approach alinement. Thisseparation of the harrow disks is objectionable because it operates toleave between them a ridge of earth Obviously, the minimum spread orseparation of the peripheries of these disks will result from theirchange of adjustment toward alinement of the shafts if the disks beardirectly upon each other in all operative posi tlons, 1n such case theseparation at their working peripheries would be so slight as to benegligible; but, by the omission of the bumper or heavy reinforce ofthat character whereby the two disks are allowed to come directly intocontact, I have found that the effect of their rubbing upon each otheris to rapidly crystallize both of them at the clrcumference of theretaining nut or bolthead by which they are bound at the center on theshaft, causing them to break at that pomt after a short period of use,several replacements being thus rendered necessary in a single seasonsuse.

I avoid both the difficulty of the common construction consisting in thespreading apart of the operating peripheries of the disks when the gangsare adjusted toward alinement of their shafts, and also the destructivecrystallization of the disks themselves as above explained, by thefeature which constitutes the present invention. This feature consistsin a thin spring metal,preferably steel,-concavo convex disk, 5, whosethickness may be even less than that of the harrow disks, and which canbe readily made by stamping from sheet steel, its curvature on theconcave side, which is mounted toward the convex side of the harrow diskbeing slightly greater than that of said convex side, so that when it isbound on to the shaft by the nut or bolt-head which would ordinarily beemployed to bind the harrow disk thereon, and when the same is tightenedup so as to press the periphery of said disk, 5, snugly against theconvex outer communicated to the harrow disk. Whom the reinforce disk,5, is thus tightened up against the harrow disk, there may remain alittle space between the proximate surfaces of the two disks over theentire area within the mere margin which bears on the outer surface ofthe harrow disk, or the two disks may be forced into actual contactimmediately back of the central binding head or nut and for somedistance outward therefrom. But even in such case, it is judged to beprobable that there is an area intermediate the circumferential bearingof the reinforce disk upon the other disk and the central area mentionedover which intermediate annular area the two disks are out of contact.But'whether this be the fact or not, and at all events, according toactual experience, whether or not the two disks are out of contact aboutthe center, the construction described results in preventing deleteriousvibration of either of the disks, thereby preventing the breaking out ofthe center, which happens, as above described, when the two harrow diskswithout reinforcement are allowed to roll directly upon each other. Afurther purpose of constructing the reinforce disk so that when firstpositioned on the convex surface of the harrow disk and before pressureis applied at the center to bind it in place, the circumferential edgeonly is in contact, is to insure thorough cont-act at that edge when thepressure is applied to the center to bind it securely. The said disk, 5,is ground upon its outer convex surface at the periphery to a knifeedge, so that it is at this knife edge that it bears laterally upon theconvex surface of the harrow disk; and when thus tightened in place, theentrance of dirt between the two disks is prevented.

I claim In a disk harrow comprising two gangs of disks, the shafts onwhich they are respectively mounted, the frame which carries the shaftsand the means for adjusting the shafts toward and from alinement witheach other, reinforces mounted on the convex side of the proximate disksof the two gangs, said reinforces consisting each of a thinconcavo-convex spring metal disk, the curvature of whose concave sidetoward the harrow disk onwhich it is mounted is normally slightlygreater than that of the convex side of said harrow disk, and means forclamping such reinforce against said convex side of the harrow disk tocause its periphery to seat snugly before contact is produced about thecenter. i

In testimony whereof, I have hereunto set my hand at Chicago, Illinois,this 3d day of July, 1913.

WINFIELD SCOTT NICHOLS.

Witnesses:

LUCY I. STONE,- M. GERTRUDE ADY.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

' Washington, I). C.

